The present invention provides a method, Web server and computer system for converging a desktop application and a Web application. The method may comprise: in response to a request from a client user for using a target desktop application, starting a desktop application initialization process on the Web server and determining an appropriate corresponding hosting server for the user; preparing and provisioning desktop application environment on the corresponding hosting server and starting the target desktop application; transmitting the corresponding hosting server's address to the client so as to make desktop application interaction between the client and the corresponding hosting server; and in response to the completion of the desktop application interaction, stopping and exiting the target desktop application on the corresponding hosting server.